1. Field of the Invention
This invention relates generally to a wheeled vehicle designed to turn about a central vertical axis. In particular, the invention relates to powered utility riding vehicles of the type useful for moving persons and their belongings within an airport terminal, amusement park, zoo, malls, parking lots and other crowded locations where rotation-in-place steering is advantageous.
2. Description of the Prior Art
Within the transportation and entertainment industries, people moving carts are often routed through crowded and busy terminals, yards or parking lots. Space is normally at a premium, resulting in limited maneuvering space. Conventional people movers typically resemble long, wide golf carts with several back seats. They are configured with two axles, one in front, the other in the rear. The rear axle is fixed to the frame of the vehicle and provides motive force via a pair of dual wheels. The front axle provides for vehicle steering via two steerable wheels which simultaneously pivot with a limited angular range.
Because there is a fixed distance between the fixed rear drive axle and the front steerable axle, a turning radius exists that far exceeds the space actually occupied by the vehicle itself. The longer the distance between front and rear axles, the larger the turning radius that is required to change directions of the vehicle. A large turning radius makes maneuvering around tight areas difficult and often dangerous. In an area where movement is constrained, a people mover with a small turn radius is advantageous.
For example, in an airport terminal, a people mover operator must often move in reverse to maneuver in tight spaces. Operators are required to look over their shoulders in order to back up. In a congested location, hazards from reversing are increased. It is often difficult, even for a skilled operator, to perform a three-point U-turn in a narrow and crowded terminal; it may be necessary to jockey back and forth many times in order to complete a U-turn.
In an airport where people are routinely moved about, any increase in maneuvering efficiency and safety amounts to significant cost savings. It is desirable, therefore, to have a vehicle with greater maneuverability to enhance the safety of the operator, the passengers and the surrounding pedestrians.
Vehicles which have increased maneuverability are known in the art. For example, an omni-directional vehicle arranged for moving people through airports is disclosed U.S. Pat. No. 6,581,703, issued to Hammonds (Jun. 24, 2003), illustrated herein as FIGS. 1-2. The Hammonds circular omni-directional people mover has two drive wheels (212) capable of independent powered forward and reverse rotation disposed along a common horizontal axis (218), which provides a zero turn radius about center vertical axis (216) for unsurpassed maneuverability. A circumferential bench seat (272) provides for carrying passengers. As shown in FIG. 3, the Hammonds omni-directional vehicle may also be used to tow a number of trailers equipped for carrying luggage. An omni-directional tractor (310) with drive wheels (312) is removably coupled to a first trailer (311) using a trolley hitch (302) that freely slides along an outer circular rail (338) of the tractor. Each trailer also includes an outer circular rail and trolley hitch for towing a subsequent trailer. However, a “train” of carts as illustrated in FIG. 3 may not be ideal for use within crowded airport terminals for moving persons between gates. In some situations, a more traditionally shaped vehicle may be preferable to these vehicles.
3. Identification of Features Provided by Some Embodiments of the Invention
A primary object of the invention is to provide a service vehicle for transporting people which is designed and arranged for enhanced maneuverability.
Another object of the invention is to provide a service vehicle for transporting people that can turn on the spot and be of the smallest physical size relative to the space it occupies.
Another object of the invention is to provide a service vehicle for transporting people which reduces the risk of accidents which may result in damage or injury to pedestrians, passengers or operating personnel.
Another object of the invention is to provide a vehicle for moving people from one location to another location which obviates the need for the operator to drive in a reverse direction.